Fuel-injected internal combustion engines are well known. It is known in the art relating to engine fuel injection systems to provide pulse dampers for reducing the noise and vibration caused by pressure pulsations in fuel lines, particularly in lines feeding individual injectors and pressurized inlet lines for high pressure fuel pumps supplying fuel for direct cylinder injection. It is known that pulsations generated by the actuation of the fuel injectors can be transmitted from the engine to the body of a vehicle by a prior art rigid fuel line extending therebetween, causing the fuel line to vibrate against the body of the vehicle and thereby generate audible and undesirable noise.
Various forms of dampers are known in the art of pulsation suppression, including expansion chambers, accumulators of gas charges, spring pistons, and spring diaphragms. However, such devices can be bulky, can be relatively costly, and may require recharging or other servicing during their anticipated life span. Thus, such pulsation dampers typically are omitted from automotive engines, and the resulting noise and vibration are either avoided or quieted in other ways or are accepted as normal with injection systems. What is needed in the art is an improved, lower cost, compact, pulsation damper system suitable for use in automotive fuel systems.
It is a principal object of the present invention to suppress transmission of pulsations through a hydraulic line.
It is a further object of the invention to suppress transmission of noise created by engine fuel injector operation through a fuel line supplying the fuel injectors.